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Title: Variational Quantum Optimization of Nonlocality in Noisy Quantum Networks
Date/Time: 17-May, 03:00PM
Venue: CQT Level 3 Seminar Room
Abstract: The inherent noise and complexity of quantum communication networks leads to challenges in designing protocols using classical methods. To address this issue, we develop a variational quantum optimization framework that simulates quantum networks on quantum hardware and optimizes the network using differential programming techniques. We use our hybrid framework to optimize nonlocality in noisy quantum networks. Using IBM quantum computers, we demonstrate our framework’s ability to maximize nonlocality on noisy quantum hardware. On a classical simulator, we investigate the noise robustness of quantum nonlocality with respect to static noise models. Our methods can reproduce known noise robustness results and find interesting new phenomena. We observe that in the presence of unital noise, maximally entangled state preparations yield maximal nonlocality, while in the presence of nonunital noise, nonmaximally entangled states can yield maximal nonlocality. As quantum computers scale, our variational quantum optimization techniques show promise of scaling beyond classical approaches. Our methods could also be implemented on quantum network hardware to automate device integration and optimize quantum communication protocols against their inherent hardware noise.